Toys R Us sells those inflatable punching clowns ... I used to set them up around my place and smack 'em as I walked by ... Great way to release pent up anger and nobody got hurt!
Also, buy you some colorful markers and the next time you feel like SI'ing ... Draw pictures and write loving thoughts of encouragment and support on yourself instead ... It may sound silly and trite, but I found this to be very helpful and healing for me!
Hoping you continue to heal well, even when and if you have a setback or two!